Friends I’ve talked to have reacted strongly, talking about rights and laws and lawsuits and confronting Customs & Border officials (the cops in this case) or ICE (they were assisting ICE in looking for an immigrant)…and then one woman said, “We’re about to discover the horrible reality that blacks in America know and understand. We don’t understand to shut up and get prone. We think we can resist a situation that doesn’t meet Constitutional standards.”

Customs and Border Protection agents met a domestic flight at John F. Kennedy Airport on Wednesday night and checked the IDs of every passenger on board, according to one traveler who documented the scene.

The incident, which took place on Delta Flight 1583 from San Francisco, was atypical for both domestic flights—on which no identification is needed to exit the airport—and international flights, where identification is checked during a customs screening after deplaning.

A spokesman for CBP told Gothamist that such checks are “not a new policy” and that it is “not unusual for us to assist our fellow law-enforcement agencies.”

CBP declined to comment on which agency it was working with on Wednesday, but said collaborative agencies might include Homeland Security, or any local or national law enforcement agency. The spokesman also said that CBP was seeking an individual, who, it turned out, was not on the flight. [CBP has since stated that the agents were assisting ICE in seeking a person with a removal order. See below for update.]